In the Spring and Autumn Period, the king of Wu was sacrificed for four years (544 BC), and the son of the king of Wu was sent to Lu (the son of the king's lifelong dream, sealed in Yanling, called Yanling). Passing by Xu, the sword that Xu Jun loves, I want it, but it's hard to say. Ji Zha understood Xu Jun's mind and decided to give him the sword. However, it is a courtesy to go out with a sword, so he must wait for him to come back to fulfill his wish. Unfortunately, prosthodontic was dead when he came back. In order to fulfill his promise, Ji Zha hung his sword on the tree in front of Heo Yun's tomb and left. The story of Ji Zi's hanging sword originated from Historical Records of Wu Taibo's Family, and there is a similar record in Xin Xu Jie Shi by Liu Xiang, a scholar of the Western Han Dynasty. Honest and clean, a promise as good as a promise, "hanging a sword and leaving Xu" is an eternal story.